Fluorescent lamp ballast with integral fuseholder and replaceable fuse



BOONE April '29, 1969 INVENTOR. (HR/STQ/HE 3 3004 5 0. B. FLUORESCENTLAMP BALLAST WITH INTEGRAL FUSEHOLDER AND REPLACEABLE FUSE Filed Feb. 9,196'? United States Patent O 3,441,889 FLUORESCENT LAMP BALLAST WITHINTEGRAL FUSEHOLDER'AND REPLACEABLE' FUSE Christopher B. Boone, Shelton,Conn. (21 Station Square, Bergenfield, NJ. 07621) Filed Feb. 9, 1967,Ser. 'No. 615,008 Int. Cl. H01h 85/24 US. Cl. 337-1 3 Claims ABSTRACT OFTHE DISCLOSURE A ballast unit for fluorescent lamps, with an integral,accessible fuseholder and a replaceable fuse. The fuseholder permits thereplacement of a burned out fuse with another fuse of the same ratingonly. The fuseholder is removably secured to the unit by eitherelliptical or U-shaped fasteners.

BACKGROUND OF THE INVENTION The present invention relates to fluorescentlamp ballasts in general and in particular to such ballasts which areprovided with integral current and heat temperature sensitive protectivedevices.

Known fluorescent lamp ballasts of the above described character areequipped with internal protectors of the resetting type or of thenon-resetting type. Both of these types of protectors are intended toprotect fluorescent lamp ballasts from abnormal conditions of heat,temperature and current. The resetting type of protector deactivates thecircuit when the heat, temperature and current rise beyond apredetermined limit. It reactivates the circuit when the temperature hasdropped to a permissible limit. The disadvantage of using this type ofprotector is the difficulty of determining the location of the faultyfixture until a subsequent deactivation takes place. In presently knownnon-resetting or integrally built-in fuse equipped ballasts the entireballast unit must be discarded and completely replaced when the fuse hasburned out, since the latter is inaccessible and cannot be replaced.This necessarily results in substantially increased maintenance costs,particularly in illumination installations employing a large number offluorescent fixtures.

SUMMARY OF THE INVENTION An important object of the invention,therefore, is to overcome the above disadvantages by providing, incombination with a fluorescent lamp ballast integral means therewithpermitting the replacement of internal heat temperature and currentsensitive protectors, said means being accessible Without anydifficulty.

A further object of the invention is to provide means of the abovedescribed character which will prevent a permanent destruction of theballast unit.

Still another object of the invention is to provide means of the abovedescribed character which will permit a permanent and positive removalof a faulty fixture from the circuit.

Yet another object of the invention is to provide a device of the abovecharacter which will make the location of a faulty fixture possible,while limiting the replacement of the fuse to the rating of the burnedout fuse.

A further object of the invention is to provide a device of the abovecharacter which will have a flexibility of location and can be mountedin any position in the ballast units casing, under the wireway cover orthrough an opening in the wireway cover to meet code requirements foraccessibility.

Another object of the invention is to provide novel means for securingthe fuseholder to the ballast units casing in a simple and time savingmanner.

r g 3,441,889 Ice Patented Apr. 29, 1969 The above and other importantobjects of the invention will become apparent from the followingdescription and the accompanying drawing illustrating one embodiment ofthe invention.

' It should be understood, however, that this is given only by way ofillustration and not of limitation, and that various changes in thedetail construction of the invention may be made, without departing fromthe scope thereof.

BRIEF DESCRIPTION OF THE DRAWING FIG. 1 is a perspective view of theballast according to the invention;

FIG. 2 illustrates means of securing the fuseholder to the panel of theballast;

FIG. 3 is yet another means of securing the fuseholder;

FIG. 3a illustrates another fastener means;

FIG. 4 shows a fuse cap with a fuse inserted therein;

FIG. 5 is a plan view of the metal flange of the fuse proper;

FIG. 6 is a section on line 6-6 of FIG. 5;

FIG. 7 is a plan view of the top portion of the fuseholder showing theopening for insertion of the flange of FIG. 5 therethrough; and

FIG. 8 is an enlarged view of the opening of FIG. 7.

DESCRIPTION OF PREFERRED EMBODIMENT Referring now to the figures indetail, the ballast unit is generally indicated by the numeral 10'. Afuseholder 12 is mounted with its enlarged part 14 extending through theopening 16 in the mounting panel 18 and is secured in place by means ofa U-shaped fastener clip 20 which is slid between raised portions 22 ofthe fuseholder on opposite sides thereof, one of said raised portions 22being shown in enlarged detail in FIG. 2 and the interior face 24 ofpanel .18. Alternatively, a fastener clip 26 of the type shown in FIG. 3or that shown in FIG. 3a may be employed.

The fastener shown in FIG. 3 is provided with tongues :28, 28a, whichafter the fastener is slid over the intermediate portion 14 in thedirection of the arrows and into contact with the lower face 24 of thepanel 18, engage said intermediate part and prevent the fastener frombeing removed, thus securing the fuseholder to the panel 18.

The fastener 30, shown in FIG. 3a, may be pre-assembled with fuseholderpart 12 and inserted through hole '16 of panel 18, so that prongs 34 and34a engage the outer face 32 of panel 18.

The horseshoe-shaped fastener 26 can be applied from the front or backof the fuseholder, depending on whether the fuseholder is mounted fromthe back of the panel 18 or from the front of the panel mounting hole.Front panel mounting makes the mounting fastener or clip 26inaccessible; back panel mounting makes possible the wiring of thefuseholder before mounting, while not as much of the fuseholderprotrudes from the ballast case. The fastener 20 is installed only onthe back after insertion of the holder from the front.

The fastener with the spring catch lancings allows the originalequipment manufacturer using the fuseholder to completely sub-assemblethe clip and insert all wiring, thus rendering the final assembly in theballast case quicker and easier.

After the fuseholder 12 has been secured in any one of the waysdescribed above, the black lead 36 of the line, from the core and coil38 is secured to one end terminal of the fuseholder 12, at 39', whileanother black lead 40 of the line is secured to the other end of thefuseholder 12, at '42 and is connected to an A.C. power source.

For the sake of clarity, a capacitor 44 is shown in phantom in theballast unit 10.

The fuseholder 12 illustrated in the drawing is of the type described inthe present applicants U.S. Patent No. 3,287,528 issued on Nov. 22,1966. It is to be clearly understood, however, that the presentinventive combination is not limited to the employment of thisparticular fuseholder, but that any other fuseholder permitting thereplacement of a fuse may be used as part of the present combination,while the fuseholder proper is integral with the ballast unit.

An important feature of the invention is the prevention of a replacementof a burned out fuse with one of a wrong rating; thus the factoryassembled fuse 46 of a predetermined rating with an integral cap 48 andinsertable in the fuseholder 12, of the same rating is provided with acap 50 formed with a pair of opposed flanges of predetermined unequalsizes 50a and 50b, which correspond only with the respective openings 54and 56 of aperture 52 of said fuseholder 12, (-FIG. 8) also of apredetermined capacity.

Thus, the fuse rating for a particular ballast unit may be controlledand assured, since a fuseholder of a predetermined rating will receiveonly a fuse of the same rating.

Although the invention has been described with reference to the aboveembodiment i.e., with the fuseholder permanently mounted on the ballastcase, the inventive concept is intended to apply to any integral holderfor use with any serviceable protective device whether it be called afuse, circuit breaker or by any other name.

Having thus described my invention, what I claim and desire to protectby Letters Patent of the United States of America is:

1. A fluorescent lamp ballast comprising:

(a) a housing having a mounting panel for a fuseholder,

(b) the mounting panel having an opening and having outer and innerfaces,

(c) the fuseholder having an enlarged part extending through the panelopening inwardly of the housing,

(d) the enlarged part having raised portions,

(e) a fastener clip wedged between the raised portions and the innerface of the mounting panel securing the enlarged part to the mountingpanel, and

(f) the fastener being a U-shaped flat member with leg portions formedwith indented prong elements extending at right angles to the respectivelegs engaging the outer face of the mounting panel.

2. The device according to claim 1, wherein the fastener clip is anelliptical flat plate having an opening therein defined by an ellipticaledge portion and a pair of spring catch lancings formed on a pair of theelliptical edge portions.

3. The device according to claim 1 wherein:

(a) the enlarged part of the fuseholder receives a fuse of predeterminedrating having an integral cap formed with a pair of opposed flanges ofsubstantially unequal sizes,

(b) the enlarged part of the fuseholder having recesses corresponding insize to the flanges, respectively, whereby the fuseholder of apredetermined rating will receive only a fuse of the same rating.

References Cited UNITED STATES PATENTS 1,940,176 12/1933 Marshall200-442 2,444,522 7/1948 Nathanson 31715 2,956,210 1 0/1960 Yatsushiro200 142 X 3,130,479 4/1964 Pleiss 29-1555 3,173,059 3/1965 Stake 317-153,275,774 9/1966 Miller 200-142 X 3,351,815 11/1967 Wolfert 317-15 XBERNARD A. GILHEANY, Primary Examiner.

H. B. GILSON, Assistant Examiner.

U.S. Cl. X.R. 337225

